37 lines
920 B
Java
37 lines
920 B
Java
/*
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* @lc app=leetcode id=134 lang=java
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*
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* [134] Gas Station
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*/
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// @lc code=start
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class Solution {
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/**
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* 本题核心为：若从i开始，计算到j时发现不行，那么从(i, j]范围内任一站点开始也不行，易进行论证
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*
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* @param gas
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* @param cost
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* @return
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*/
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public int canCompleteCircuit(int[] gas, int[] cost) {
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int start = 0, sum = 0, curIdx = 0;
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while(start < gas.length) {
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if(curIdx - start == gas.length) {
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return start;
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}
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int pos = curIdx % gas.length;
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if(sum + gas[pos] - cost[pos] < 0) {
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curIdx++;
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start = curIdx;
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sum = 0;
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} else {
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sum += gas[pos] - cost[pos];
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curIdx++;
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}
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}
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return -1;
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}
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}
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// @lc code=end
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